Flat bed web printing press



Sept. 11,. 1934. P. F. COX 1,973,464

FLAT BED WEB PRINTING PRESS Filed May 22, 1935 II M L IIL by E 19m N w Y "V 1! WWW Patented Sept. 11, 1934 1,973,464

UNITED ATES PTN 1,973,464 FLAT BED was PRINTING PRESS Paul F. Cox, Chicago, 111., assignor to The Goss Printing Press Company, Chicago, 111., a corporation of Illinois Application May 22, 1933, Serial No. 672,303

9 Claims. (01; 101'-256) This invention relates to flat bed Web printing ders 2 and 2a back and forth over the beds, by presses such, for instance, as shown in my Patmeans of pitmen 3:; connecting the crossheads ents Nos. 988,548; 1,475,566 and others. with crank gears (not shown). By rocking the The object of the invention is to-prevent smut eccentrics 2c, 2d the cylinders are thrown on or offset from one side of a freshly printed web impression during one stroke of the crossheads onto the perfecting impression cylinder, and from and thrown off impression during the other the latter onto the opposite side of the web. stroke.

For this purpose Iprovide means wherebywhen The Web w may be fed from a web roll, not w the impression cylinder is thrown off impression shown, and directed by suitable means to and 10 the portions of the web underlying the perfecting over a guide 9 and under guide 9 on the crossimpression cylinder and between theguide rolls heads adjacent cylinder 2, then under the cylinof the opposite sides thereof will be clear of both der to a roller 0 on the crosshead and thence up the cylinder and the type, but the cylinder will over a guide 9 on the crosshead beside cylinder be maintained in accurate mesh relation with the 2; thence out over a stationary guide 9 mounted bed rack by means of an auxiliary rack section on the press frame; up over a guide 9 on the which remains continually in mesh with the cylframe; thence inwardly to and over a guide 9 inder gear but raises and lowers in accordance on the crossheads adjacent cylinder 211; down unwith the movement of the cylinder to ofi and der guide g beside cylinder 2a to a guide g on on impression positions, such rack section pree eretseheeid a the DI Side Of cylinder 20 20 venting back lash and also preventing the cylinand up over guide 9 and thence to the web dedcr from becoming disengaged or out of time with livery devices. the bed rack when raised high enough'to permit When the cylinders are on impression and the web to pass beneath such cylinder during the moving across the beds 1, 1a, the web is stopped web shifting operations without coming into conbetween the feed and delivery by the action of 25 tact therewith. devices (not shown). 'While the cylinders are 80.

I will explain one practical embodiment of the impression the Web is Shifted forward y invention with reference to the accompanying d evi s. T n ral c nstructi n and ardrawing to facilitate an understanding of the in-" ane ento the af a d parts and the p vention by those skilled in the art.. In theclaims tier! thereof a Well known, and y be as sh w 30 the essentials of the invention and the novel fea and described in my aforesaid pat ts; and theretures of construction and novel combinationsof O I need I further detailed illustration o parts for which protection is desired, are surnnl'a herein marizei The first printed side of the web would ordi-' In th drawing; narily come into contact with the surface of the 35 Fig. 1 is a diagrammatic side elevation of part impressionwlinder and Soma of the fresh mk of a flat bed web printing press equipped with Qn W b would adhere to the Surface of the my invention c'ylinderand smut the same; and such smut Fig. 2 is an enlarged diagrammatic View partly P pressedby the cylmgler the pass in section showing the parts in positions assumed g thereunder produces Offset and 5100115 the i when the impression cylinder is off impression appearance the'perfeqted Shae and the Web is being shifted thereunder; I To prevent this smutting I so locate the guide Fig. 3 is a detail side view of part of the bed s 98 e 99 on the cfossheads a the lower per pheriesthereof are in a plane slightly above lack and movable rack Sectlon' the plane o the printing surface of the ype T on 45 t 4 a top plan View ofpartlof the 9 rack" the bed la: and slightly below the mane of the 100 5 1s a transverse seamen on the mm 5 lower periphery of the cylinder 2a when the latter is raised or' .off impression position, as indicated The type of press Shown m the drawmg and Fig. 2, so that the web 10 passing between the in the patents referred to has parallel type beds. 11 8 and o during the hifting operation will 50 1, arranged one over the other n a sulta'ble not contact with the cylinder nor with the type main m COQPQTatmg with these'beds are (see Fig; 2), and therefore during the shifting of. traveling impression cylinders 2, a. mounted in the'web between impressions'the printed side of eccentric bearings 20, 211 in CIOSShBQdS 3 which the eb dues not ontact. with the periphery of are supported in guideways in the side frames of the cylinder 2a and the latter will not be smeared 5 the press and are reciprocated to move the cylinor smutted.

In Fig. 1 the cylinder is shown on impression, but in Fig. 2 th cylinder is shown 01f impression and raised high enough so that the web does not touch the cylinder while being shifted, and the guide rollers g and g are placed high enough to permit the web to be shifted without touching the type form.

In order to permit the cylinder 20: to be raised high enough to avoid smutting of the web during the shifting thereof yet maintain a constant and true pitch line mesh position with relation to the rack, I provide an auxiliary bed rack or section 6a, which is preferably mounted within a longitudinal slot in the bed rack 6, see Figs. 3-5.

The auxiliary rack 6a is toothed similar to the bed rack 6 and when the auxiliary rack is in lowered or depressed position its teeth exactly coincide with the teeth of the bed rack 6. The auxiliary rack 6a is made vertically movable so that it can raise as and when the cylinder rises to off impression, and can be lowered by and with the cylinder gear when the cylinder is on impression. lhe auxiliary rack may be raised and lowered by any suitable means. As shown it is raised by means of springs inserted in recesses f in the adjacent side members F of the press (Figs. 2 and 5). The auxiliary rack may be accurately guided in its vertical movements by pins 66 attached thereto and engaging sockets f in the member F. The springs cause the auxiliary rack to follow the cylinder 2d when it rises off impression and as the teeth of auxiliary rack 6a remain constantly in mesh with the cylinder gear 2g prevent any back lash of the cylinder and keep it accurately timed in relation to the bed rack while rising or lowering and while in its raised or off impression position, and allows such cylinder to be raised high enough to clear the web between the cylinders g and g and while such web is being transferred through the press.

While the invention is primarily designed for use in fiat bed web perfecting presses of the character set forth it is applicable to other types of bed and cylinder machines in which the printing mechanism is thrown on impression during the shifting of the web or sheet.

I claim:-

1. In a bed and cylinder web printing press having a cylinder and bed, a bed rack, a cylinder gear meshing with the bed rack, guides for directing a web between the cylinder and bed, and means for throwing impression on and off; an auxiliary rack extending lengthwise of and vertically movable relative to the rack and to and from the cylinder and engaging the cylinder gear and means for keeping the auxiliary rack in mesh with said gear, whereby the cylinder is kept in accurate mesh relation with the bed rack when the impression is thrown off.

2. In mechanism as set forth in claim 1, the bed rack being longitudinally slotted and the auxiliary rack being movably mounted in the slot of the bed rack.

3. In a press as set forth in claim 1, the web guides at opposite sides of the cylinder having their lower peripheries disposed in a plane slightly above the plane of the printing surface andslightly below the plane of the cylinder when it is thrown off impression.

4. In a bed and cylinder web printing press having a cylinder and bed, a bed rack, a cylinder gear meshing with the bed rack, guides for directing a web between the cylinder and bed, and means for throwing impression on and off; an auxiliary rack extending lengthwise of and vertically movable relative to the rack and to and from the cylinder and engaging the cylinder gear, and means for keeping the auxiliary rack in mesh with said gear whereby the cylinder is kept in accuratefrelation with the bed rack when the impression is thrown off, the web guides adjac'ent the cylinder being so disposed that when the impression is thrown off the web passing between said guides is clear both of the periphery of the cylinder and the printing surface.

5. In mechanism as set forth in claim 4, the bed rack being longitudinally slotted and the 9d auxiliary rack being movably mounted in the slot of the bed rack.

6. In a fiat bed and traveling cylinder web printing press having means for reciprocating the cylinders over the beds and web guides for directing web successively between the beds and cylinders including guides mounted on the crossheads at opposite sides of the cylinders, and means for throwing the cylinders on and off impression; an auxiliary bed rack extending lengthwise of and movable relative to the rack and to and from the perfecting cylinder and engaging the cylinder gear, and means for keeping the auxiliary rack in mesh with said gear, whereby the cylinder is kept in accurate relation with the bed rack, the parts being so disposed that when the cylinder is thrown off impression the web passed between the guides is free both of the peripheries of the cylinder and the type of the printing surface.

7. In mechanism as set forth in claim 6, the bed rack for the perfecting cylinder being slotted and the auxiliary rack movably mounted in the slot of said bed rack.

8. In a flat bed and traveling cylinder web 115 printing press having means for reciprocating the cylinders over the beds, longitudinally slotted bed racks, cylinder gears meshing with the bed racks, guides for directing web successively be tween the beds and cylinders including guides mounted on the crossheads at opposite sides of the cylinders, and means for throwing the cylinders on and 01f impression; an auxiliary mounted in the slot in the perfecting cylinder bed rack and movable relative tothe bed rack to and from the perfecting cylinder and engaging said cylinder gear, and means for yieldingly holding said auxiliary rack in engagement with said gear, whereby said perfecting cylinder is kept in accurate relation with the bed rack when thrown off impression; the parts being so disposed that when the perfecting cylinder is thrown off impression the web passing thereunder is clear both of the periphery of the cylinder and the printing surface.

9. In a single acting stationary bed and traveling cylinder press having means whereby impression is thrown off during one stroke of the cylinder; a gear on the cylinder, a compound bed rack meshing with said gear and comprising a fixed gear portion and a movable gear portion aligned with the fixed gear portion, and means for holding the movable portion yieldingly in full mesh engagement with the cylinder gear both during the impression and while the 1145.

impression is thrown off.

PAUL F. COX. 

